WO2021090747A1

WO2021090747A1 - Distributed antenna and distributed antenna system

Info

Publication number: WO2021090747A1
Application number: PCT/JP2020/040507
Authority: WO
Inventors: 翔熊谷; 森本　康夫; 健茂木; 圭祐新井; 加賀谷　修
Original assignee: Ａｇｃ株式会社
Priority date: 2019-11-06
Filing date: 2020-10-28
Publication date: 2021-05-14
Also published as: JPWO2021090747A1; EP4057446A4; US11949160B2; TW202127820A; US20220255234A1; CN114600316A; EP4057446A1

Abstract

A distributed antenna 20 comprises: a belt-shaped member 1 that extends in a belt shape and has a sheet-shaped dielectric, a first surface which is one surface of the dielectric, and a second surface on the opposite side from the first surface; a transmission path 3 that is provided on one of the first surface and the second surface, or is provided between the first surface and the second surface; and a plurality of antenna elements 2 that are electrically connected to the transmission path 3 and are positioned in a distributed manner on one of the first surface and the second surface, or are electrically connected to the transmission path and are positioned in a distributed manner between the first surface and the second surface.

Description

Distributed Antenna and Distributed Antenna System

This disclosure relates to a distributed antenna and a distributed antenna system.

Since the millimeter wave band used for antennas of 5G wireless base stations and the like has high straightness of radio waves, stable communication becomes difficult if the antennas are installed centrally in one place. Further, since the installation of wireless base stations is restricted depending on the device weight, device dimensions, etc., it may be difficult to increase the number of wireless base stations installed in order to widen the coverage area.

According to the distributed antenna system of Patent Document 1, by providing a base band portion that generates a high-frequency signal and a plurality of antennas that are separated from the base band portion and arranged in a radio dead zone or the like, the building premises and the underground street While realizing stable wireless communication in radio dead zones such as in factories, the coverage area can be expanded without being restricted by the installation of wireless base stations.

JP-A-2018-067855

However, in the conventional technology, for example, when installing a plurality of antennas on a wall of a building, work such as attaching each antenna to the wall one by one is required. Furthermore, it is also necessary to carry out work such as crawl and fix the transmission line connected to these antennas on a wall or the like. Therefore, there is a problem that the work associated with the installation of the antenna becomes complicated.

The present disclosure has been made in view of the above, and an object of the present disclosure is to obtain a distributed antenna that is easy to install.

In order to solve the above-mentioned problems and achieve the object, the distributed antenna according to the present disclosure includes a plate-shaped dielectric and a first surface which is one surface of the dielectric and a first surface opposite to the first surface. A transmission having two surfaces and extending in a band shape and provided on any surface of the first surface and the second surface, or provided between the first surface and the second surface. The line and the transmission line are electrically connected and distributed on any of the first surface and the second surface, or are electrically connected to the transmission line and the first surface. It is provided with a plurality of antenna elements dispersedly arranged between the second surface and the second surface.

According to the distributed antenna of the present disclosure, it is possible to obtain a distributed antenna that is easy to install.

The figure which shows the configuration example of the distributed antenna and the base station which concerns on embodiment of this disclosure. The figure which shows the arrangement example of a plurality of antenna elements branch-connected to a transmission line The figure which shows the arrangement example of the antenna element 2 cascade connected to the transmission line. The figure which shows the arrangement example of the signal processing circuit arranged on the transmission line The figure which shows the structural example of the band-shaped member 1 which fixed (laminated) the rigid part 1B to the flexible part 1A. The figure which shows the structural example of the strip-shaped member 1 which connected the flexible part 1A and the rigid part 1B provided at the position away from the flexible part 1A by a connector 1C or the like. The figure for demonstrating the example of arranging a plurality of antenna elements in a distributed manner. The figure which shows the structural example of the signal processing circuit The figure which shows the connection example of the amplifier module provided with a plurality of signal processing circuits, and a plurality of antenna elements connected to an amplifier module. The figure which shows the example when the amplifier module is provided in the strip-shaped member. Diagram for explaining the communicable distance when a low noise amplifier is not provided Diagram for explaining the communicable distance when a low noise amplifier is provided The figure which shows the configuration example which extends the communicable distance by providing a plurality of low noise amplifiers. Diagram schematically showing a branch-connected distributed antenna The figure which shows typically the distributed antenna of a cascade connection type Enlarged view of a branch-connected distributed antenna Diagram for explaining the image when a branch connection type distributed antenna is installed on the ceiling surface in the station yard Diagram for explaining the image when a cascade connection type distributed antenna is installed on the ceiling surface in the station yard. The figure for demonstrating the modification of the signal processing circuit The figure which shows the 1st modification of the band-shaped member The figure which shows the 2nd deformation example of a band-shaped member Diagram showing a configuration example of a flexible module The figure which shows the configuration example of the distributed antenna for a repeater The figure which shows the arrangement of the antenna and the pillar in this test The figure which shows the structure of the antenna used in this test The figure which shows the antenna characteristic of the antenna used in this test A table showing the measurement results (S21) from this test for each column installation condition. Graph showing the measurement result (S21) by this test for each pillar installation condition Top view of the flexible antenna according to the embodiment The figure which shows an example of the cross-sectional structure of the flexible antenna which concerns on embodiment. The figure which shows another example of the cross-sectional structure of the flexible antenna which concerns on embodiment. The figure which shows the installation example to the pillar of the flexible antenna which concerns on embodiment FIG. 32 is a cross-sectional view of the flexible antenna and the XY plane shown in FIG. The figure which shows the 1st modification of the antenna pattern in the flexible antenna which concerns on embodiment The figure which shows the 2nd modification of the antenna pattern in the flexible antenna which concerns on embodiment The figure which shows the 3rd modification of the antenna pattern in the flexible antenna which concerns on embodiment The figure which shows the 1st example of the antenna characteristic of the flexible antenna which concerns on embodiment The figure which shows the 1st example of the antenna characteristic of the flexible antenna which concerns on embodiment The figure which shows the 2nd example of the antenna characteristic of the flexible antenna which concerns on embodiment The figure which shows the 2nd example of the antenna characteristic of the flexible antenna which concerns on embodiment The figure which shows the 3rd example of the antenna characteristic of the flexible antenna which concerns on embodiment. The figure which shows the 3rd example of the antenna characteristic of the flexible antenna which concerns on embodiment. The figure which shows the 4th example of the antenna characteristic of the flexible antenna which concerns on embodiment. The figure which shows the 4th example of the antenna characteristic of the flexible antenna which concerns on embodiment. The figure which shows the 5th example of the antenna characteristic of the flexible antenna which concerns on embodiment The figure which shows the 5th example of the antenna characteristic of the flexible antenna which concerns on embodiment The figure which shows the 4th modification of the antenna pattern in the flexible antenna which concerns on embodiment The figure which shows the installation example to the pillar of the flexible antenna shown in FIG. 42 The figure which shows an example of the antenna characteristic of the flexible antenna shown in FIG. 42. The figure which shows an example of the antenna characteristic of the flexible antenna shown in FIG. 42.

Hereinafter, the distributed antenna according to the embodiment of the present disclosure will be described in detail with reference to the drawings. Hereinafter, embodiments according to the present disclosure will be described with reference to the drawings.

FIG. 1 is a diagram showing a configuration example of a distributed antenna and a base station according to the embodiment of the present disclosure. The distributed antenna system 300 shown in FIG. 1 includes a base station 10, a distributed antenna 20, and a communication line 30. For example, a base station 10 is connected to the distributed antenna 20 via a communication line 30. The distributed antenna 20 is an antenna for a base station such as 5G.

The distributed antenna 20 includes a band-shaped member 1 which is a band-shaped dielectric, and a plurality of antenna elements 2 which are distributed and arranged on the band-shaped member 1. Further, the distributed antenna 20 is a transmission line 3 which is a line for signal transmission arranged on the band-shaped member 1 and connected to the communication line 30 and connecting a plurality of antenna elements 2, and the antenna element 2 and the base station 10. It is provided with a signal processing circuit 4 for processing signals transmitted between them. The transmission line 3 may be composed of, for example, a substrate integrated waveguide, a so-called SIW (Substrate Integrated Waveguide), a strip line on a multilayer board, or the like. In this case, the transmission line 3 is provided between the first surface and the second surface of the strip-shaped member 1. Details of the first surface and the second surface of the strip-shaped member 1 will be described later. Further, the transmission line 3 may have a structure (for example, a microstrip line) provided on either the first surface or the second surface.

The strip-shaped member 1 is, for example, a flexible substrate having a strip-shaped dielectric as a core material. A flexible substrate is a substrate that has flexibility that allows it to be bent, can be repeatedly deformed with a weak force, and has the property of maintaining its electrical characteristics even when deformed. The flexible substrate is thinner than a general rigid substrate and has excellent workability, so that it is possible to process a complicated shape. The flexible substrate has, for example, a structure in which a conductor foil is bonded to a thin-film dielectric having a thickness of 12 μm to 500 μm. As the dielectric, a material called solder resist (resist / photoresist) or coverlay (Coverlay), polyimide, polyester or the like is used. When the dielectric contains a resin layer (that is, when a part or all of the dielectric is a resin layer), the resin that can be contained in the dielectric is, for example, a fluororesin such as a tetrafluoroethylene polymer. There is. As the material of the conductor foil, for example, gold, silver, copper, aluminum, platinum, chromium and the like are used. The strip-shaped member 1 may be formed of a rigid substrate having a strip-shaped dielectric as a core material instead of the flexible substrate. Examples of the rigid substrate include a glass composite substrate, a glass epoxy substrate, an alumina substrate, a composite substrate and the like. The strip-shaped member 1 may have a structure in which a plurality of dielectric layers are stacked. At this time, the plurality of antenna elements 2 are electrically connected to the transmission line and are provided between the first surface and the second surface of the strip-shaped member 1. That is, the antenna element 2 may be embedded in the multilayer board. Further, the plurality of antenna elements 2 may be provided on the first surface or the second surface.

The antenna element 2 is suitable for transmitting and receiving radio waves in a high frequency band (for example, over 1 GHz to 300 GHz) such as microwaves and millimeter waves. The antenna element 2 can be applied to, for example, a V2X communication system, a 5th generation mobile communication system (so-called 5G), an in-vehicle radar system, and the like, but the applicable system is not limited to these. As the frequency range, for example, for ITS (Intelligent Transport Systems) (5.89 GHz), for 5 G (28 GHz band, 3.6 to 6 GHz band, 39 GHz band), Wi-Fi (2.4 GHz, It may be for 5 GHz).

Next, an example of arranging the antenna element 2 and the like on the strip-shaped member 1 will be described with reference to FIGS. 2 to 4.

FIG. 2 is a diagram showing an arrangement example of a plurality of antenna elements branched and connected to a transmission line. The strip-shaped member 1 shown in FIG. 2 includes a transmission line 3 which is a first transmission line, an antenna element 2 arranged on the transmission line 3 (for example, a tip portion of the transmission line 3), and 1 branching from the transmission line 3. Alternatively, a transmission line 3a, which is a plurality of second transmission lines, and an antenna element 2 arranged on the transmission line 3a (for example, the tip of the transmission line 3a) are provided. Providing the antenna element 2 on a plurality of transmission lines 3a branched from one transmission line 3 in this way is referred to as a "branch connection type". The "branch from transmission line 3" includes a simple branch (impedance matched) and a branch by a synthesizer such as a Wilkinson coupler or a distributor.

According to the branch connection type, since a plurality of antenna elements 2 can be arranged around the transmission line 3 linearly wired to the band-shaped member 1, the degree of freedom in the arrangement layout of the antenna elements 2 is improved. Therefore, for example, the width of the band-shaped member 1 in the direction orthogonal to the extending direction of the band-shaped member 1 can be widened, and the plurality of antenna elements 2 can be arranged in a plane shape by utilizing the widened portion. Therefore, the branch connection type is particularly effective when expanding the coverage area in a planar manner.

FIG. 3 is a diagram showing an arrangement example of the antenna element 2 cascaded to the transmission line. The strip-shaped member 1 shown in FIG. 3 is provided with a transmission line 3 and two antenna elements 2 arranged on the transmission line 3 (for example, a tip portion of the transmission line 3 and a portion other than the tip portion). Providing a plurality of antenna elements 2 on one transmission line 3 in this way is referred to as a "cascade connection type".

According to the cascade connection type, the structure of the transmission line 3 can be simplified, and the width of the strip-shaped member 1 in the direction orthogonal to the extending direction of the transmission line 3 can be narrowed. Therefore, it is particularly effective when the coverage area is linearly expanded without making the user of the mobile terminal aware of the distributed antenna 20.

FIG. 4 is a diagram showing an arrangement example of a signal processing circuit arranged on a transmission line. The band-shaped member 1 shown in FIG. 4 includes a transmission line 3, an antenna element 2 arranged on the transmission line 3 (for example, a tip portion of the transmission line 3), a transmission line 3a branching from the transmission line 3, and for example transmission. An antenna element 2 arranged on the line 3a (such as the tip of the transmission line 3a) and a signal processing circuit 4 provided on the transmission line 3, for example, are provided.

In FIG. 4, one of the two signal processing circuits 4 is provided on the transmission line 3, and the other is provided at a position where the transmission line 3a branches from the transmission line 3. The arrangement position of the signal processing circuit 4 is not limited to the position shown in the illustrated example, and may be, for example, an intermediate portion of the transmission line 3a, the vicinity of the transmission line 3, the vicinity of the transmission line 3a, or the like. Further, the number of signal processing circuits 4 is not limited to two, and can be appropriately changed depending on the application, specifications, and the like of the distributed antenna 20.

FIG. 4 illustrates a plurality of antenna elements 2 connected in a branch. Then, by providing a signal processing circuit 4 having, for example, an AMP (Amplifier), a switch, a mixer, a DAC (Digital to Analog Converter), an ADC (Analog to Digital Converter), or the like, a signal processing circuit 4 is provided near these antenna elements 2. It can compensate for millimeter waves with large transmission loss. The same effect can be obtained when the signal processing circuit 4 having any (part) of AMP, switch, mixer, DAC, and ADC is provided near the antenna element 2. Details of the AMP, switch, mixer, DAC, ADC and the like will be described later.

Next, with reference to FIGS. 5 and 6, a configuration example of the strip-shaped member 1 in which the flexible core member and the rigid core member are combined will be described.

FIG. 5 is a diagram showing a configuration example of a strip-shaped member 1 in which a rigid portion 1B is fixed (laminated) to a flexible portion 1A, and FIG. 6 shows a flexible portion 1A and a rigid portion 1B provided at a position away from the flexible portion 1A. It is a figure which shows the structural example of the band-shaped member 1 connected by the connector 1C and the like. The flexible portion 1A has, for example, a core portion 1b which is a plate-shaped dielectric layer and a conductive portion 1a which is a conductive member (for example, a copper anchor) provided on the upper and lower surfaces of the core portion 1b. Of the two conductive portions 1a, one conductive portion 1a is provided on the first surface 1b1 which is one surface of the core portion 1b, and the other conductive portion 1a is opposite to the first surface 1b1 of the core portion 1b. It is provided on the second surface 1b2 on the side. The transmission line 3 is provided on any surface of the first surface 1b1 and the second surface 1b2, or is provided between the first surface 1b1 and the second surface 1b2. Further, the antenna element 2 is electrically connected to the transmission line 3 and is dispersedly arranged on any surface of the first surface 1b1 and the second surface 1b2. The configuration of the flexible portion 1A is not limited to this, and may be, for example, a multilayer structure using two or more dielectric layers and two or more conductive members.

These strip-shaped members 1 are composed of, for example, a rigid flexible substrate, and the rigid flexible substrate is a substrate that has the advantages of both a rigid substrate and a flexible substrate, such as ease of component mounting and three-dimensional arrangement by bending. The rigid flexible substrate includes, for example, a rigid portion 1B which is a rigid core member on which parts and the like are mounted, and a flexible portion 1A which is a flexible member (flexible core member) having flexibility.

The strip-shaped member 1 of FIG. 5 has a structure in which a rigid portion 1B is laminated on a flexible portion 1A. In this case, the size of the rigid portion 1B is preferably such that the flexibility of the flexible portion 1A is not impaired.

In the strip-shaped member 1 of FIG. 6, for example, the rigid portion 1B is arranged between two separated flexible portions 1A, and the flexible portion 1A and the rigid portion 1B are electrically connected by using the connector 1C and the jumper wire 1D. Has a structure that is The jumper wire 1D may also serve as a part of the flexible portion 1A.

Next, with reference to FIG. 7, an example in which a plurality of antenna elements 2 are distributed and arranged will be described. FIG. 7 is a diagram for explaining an example in which a plurality of antenna elements are distributed and arranged. FIG. 7 shows a cross section of the building wall 100 and a distributed antenna 20 installed on the surface of the building wall 100. When the distributed antenna 20 has the flexible strip-shaped member 1, the strip-shaped member 1 can be provided along the surface of the convex portion 201 even if the convex portion 201 is on the surface of the wall 100 of the building. Further, the distributed antenna 20 may be installed at the boundary between the surface (flat surface 202) where the convex portion 201 is not provided and the convex portion 201 on the surface of the wall 100 of the building while minimizing the gap. it can.

For fixing the distributed antenna 20 to the wall 100, for example, an adhesive material may be used, or a fastening member such as a bolt or nut may be used. Further, the distributed antenna 20 may be installed on the wall 100 by hooking the distributed antenna 20 on a hook-shaped member protruding from the wall 100. As a result, the distributed antenna 20 can be easily installed, and for example, the distributed antenna 20 is installed on the wall 100 of the building only during the period of the event held irregularly, and the distributed antenna 20 is removed after the event is completed. Can be done. Therefore, it is possible to use the distributed antenna 20 on demand without permanently installing the distributed antenna 20. In addition, when installing a conventional distributed antenna at an event venue, etc., each antenna must be installed individually on a wall, etc., which complicates the installation work and also separates the transmission line connected to the antenna. Need to lay. Therefore, when using millimeter-wave band radio waves, a great deal of man-hours and labor are required to expand the coverage area, and even after the event is over, a lot of work time is required for work such as removing those antennas. I need to spend. On the other hand, according to the distributed antenna 20 according to the present embodiment, since a plurality of antenna elements 2, transmission lines 3, and the like are installed on the strip-shaped dielectric, the strip-shaped member 1 is attached to the wall 100 of the building and the like. The coverage area can be easily expanded simply by connecting to the base station 10. In addition, since the band-shaped member 1 can be collected simply by removing it, it is easy to restore the current state after the event.

Next, a configuration example of the signal processing circuit 4 will be described with reference to FIGS. 8 and 9. FIG. 8 is a diagram showing a configuration example of the signal processing circuit 4. "Digital" in the figure means a transmission line of a digital signal. “DC” means, for example, wiring that supplies DC power. The signal processing circuit 4 includes, for example, a DAC 401 that is a converter that converts a digital signal transmitted from a base station 10 into an analog signal and outputs it to a mixer 403, a local transmitter 402 that is a local signal source, and a local transmitter 402. It is provided with a mixer 403 which is an up-converter that up-converts a signal from DAC 401 by a local signal from. Further, the signal processing circuit 4 transmits the power amplifier 404, which is a signal amplifier that amplifies the signal output from the mixer 403 and inputs it to the antenna element 2 via the switch 405 and the directional coupler 406, and the signal processing circuit 4. It is provided with a switch 405 as a means for selecting reception and reception, and a directional coupler 406. Further, the signal processing circuit 4 amplifies the signal received by the antenna element 2 and communicates with the low noise amplifier 407 input to the mixer 409 via the switch 408 with a path for monitoring and feeding back the received / transmitted signal. It is provided with a switch 408 which is a means for selecting reception of a signal. Further, the signal processing circuit 4 is a mixer 409 which is a down converter that down-converts the signal from the low noise amplifier 407, and a converter that converts the analog signal transmitted from the mixer 409 into a digital signal and transmits it to, for example, the base station 10. It is equipped with a certain ADC 410.

According to the signal processing circuit 4, by providing the DAC 401 and the ADC 410, communication by a digital signal is possible between the base station 10 and the signal processing circuit 4, so that signal deterioration is suppressed. Therefore, the communicable distance from the base station 10 to the signal processing circuit 4 can be made relatively long, and a plurality of antenna elements 2 can be distributed and arranged at locations remote from the base station 10.

Further, according to the signal processing circuit 4, for example, by providing the mixer 403 and the mixer 409, the signal transmitted between the base station 10 and the signal processing circuit 4 can be handled at a low frequency, so that the base station 10 and the signal processing circuit can be handled. The transmission loss between 4 and 4 can be reduced. Therefore, the communicable distance from the base station 10 to the signal processing circuit 4 can be lengthened, and a plurality of antenna elements 2 can be distributed and arranged at locations remote from the base station 10.

By combining the DAC 401 and the ADC 410 with the mixer 403 and the mixer 409 in this way, for example, in a state where the base station 10 is installed in an equipment room such as a stadium, the distance from the base station 10 to the spectator seats of the stadium is about several tens of meters to several hundred meters. , The communication line 30 can be routed to transmit a signal to the distributed antenna 20 laid in the spectator seats of the stadium. As a result, wireless communication using, for example, millimeter waves becomes possible between a plurality of mobile terminals existing in the audience seats. Further, even when a plurality of mobile terminals are dispersed and exist in a range of several tens of meters in a spectator seat such as a stadium, wireless communication can be performed even in a wide range by using the signal processing circuit 4. Compensate for the level and enable wireless communication.

The signal processing circuit 4 includes a mixer 403, a mixer 409, a DAC 401, an ADC 410, and the like. Among these, the signal processing circuit 4 may be configured to include only the mixer 403 and the mixer 409, or may be configured to include only the DAC 401 and the ADC 410. Even in this case, it is possible to increase the communicable distance from the base station 10 to the signal processing circuit 4, and it is possible to obtain the effect that the configuration of the signal processing circuit 4 is simplified and the reliability is improved.

Next, an example in which a plurality of signal processing circuits 4 are provided for one strip-shaped member 1 will be described with reference to FIGS. 9 and 10.

FIG. 9 is a diagram showing a connection example of an amplifier module provided with a plurality of signal processing circuits and a plurality of antenna elements connected to the amplifier module. The amplifier module 400 shown in FIG. 9 includes, for example, four signal processing circuits 4, and each of these signal processing circuits 4 is connected to the antenna element 2 via a transmission line 3. The number of signal processing circuits 4 included in the amplifier module 400 is not limited to four. Further, when the number of signal processing circuits 4 of the amplifier module 400 is two or more, the signal processing circuits 4 can be realized by arranging the signal processing circuits 4 in parallel as shown in FIG. Further, in FIG. 9, a module including a plurality of signal processing circuits 4 is referred to as an amplifier module 400, but the signal processing circuit 4 itself may be read as an amplifier module 400. Therefore, one signal processing circuit 4 may be referred to as an amplifier module 400.

FIG. 10 is a diagram showing an example in the case where the amplifier module is provided on the strip-shaped member. By providing the amplifier module 400 on the band-shaped member 1, the low noise amplifier 407 and the power amplifier 404 of the signal processing circuit 4 compensate for the signal transmission loss by the transmission line 3. Therefore, the distance from the amplifier module 400 to the plurality of antenna elements 2 can be significantly extended. The amplifier module 400 shown in FIG. 10 may be configured to include, among the functions of the signal processing circuit 4, a low noise amplifier 407, a power amplifier 404, a switch 405, a directional coupler 406, and the like.

When the amplifier module 400 is provided in a place other than the strip-shaped member 1, it is necessary to connect the amplifier module 400 to the antenna element 2, but according to the configuration example shown in FIG. 10, the work becomes unnecessary. Since the installation work of the distributed antenna 20 is facilitated and wiring connection mistakes by the operator do not occur, deterioration of communication quality can be suppressed. Further, according to the configuration example shown in FIG. 10, for example, since the low noise amplifier 407 can be placed in the vicinity of the antenna element 2, it is possible to suppress the deterioration of the signal due to the transmission loss from the antenna element 2 to the low noise amplifier 407.

Further, as compared with the case where the amplifier module 400 is provided in a place other than the strip-shaped member 1, the design of the distributed antenna 20 itself is improved, and the design of the building or the like is not impaired, and the distributed antenna 20 can be used. You can increase the number of places.

Further, by providing the amplifier module 400 in the band-shaped member 1, the heat generated by the low noise amplifier 407, the power amplifier 404, etc. is transferred to the transmission line 3 and the band-shaped member 1, so that the transmission line 3 and the band-shaped member 1 serve as a radiator. Function. Therefore, it is possible to prevent the amplifier module 400 from failing due to heat. Further, by providing the amplifier module 400 on the strip-shaped member 1, for example, even if the heat-dissipating member (fins or the like) is installed in an inconspicuous place on the wall surface, the transmission line 3 and the strip-shaped member 1 can be connected to the power amplifier 404 or the like. It can be used as a heat conduction path for transferring the generated heat to the heat dissipation member.

The strip-shaped member 1 may be provided with power wiring (for example, wiring for supplying DC power) for supplying power for driving the amplifier module 400 or the signal processing circuit 4. As a result, it is not necessary to lay the power wiring separately from the band-shaped member 1, and the working time can be significantly reduced even when the distributed antenna 20 is installed in a wide range while suppressing the deterioration of the appearance of the distributed antenna 20.

FIG. 11 is a diagram for explaining a communicable distance when a low noise amplifier is not provided. FIG. 12 is a diagram for explaining a communicable distance when a low noise amplifier is provided. FIG. 13 is a diagram showing a configuration example in which the communicable distance is extended by providing a plurality of low noise amplifiers. The horizontal axis of FIGS. 11, 12 and 13 represents the distance from the mobile terminal, and the vertical axis of FIGS. 11, 12 and 13 represents the electric power output from each device. The dashed line represents the signal level and the solid line represents the noise level. The conditions for acquiring these data are as follows. (conditions)
LNA of FIGS. 11 and 12: Gain = 15 dB / NF = 4 dB
First stage LNA in Fig. 13: Gain = 45dB / NF = 6dB
LNA after the second stage in FIG. 13: Gain = 30dB / NF = 5dB
Mobile Power: 20dBm
Antenna Gain: 12dBi
Distance to Tx: 5m
Feeder loss: 30dB / m
Mixer: Gain = 10dB / NF = 15dB
SN ratio after Mixer: 10dB

From FIG. 11, when the low noise amplifier 407 is not provided, the signal level is low, and the distance from the mobile terminal to the antenna element 2 is 5 m, the transmission distance from the antenna element 2 as the receiving system to the mixer 409 is 0.8 m. Only to a certain extent can be secured. The same applies to the transmission system. On the other hand, when the low noise amplifier 407 is provided, as shown in FIG. 12, when the signal level is high and the distance from the mobile terminal to the antenna element 2 is 5 m, the antenna element 2 as the receiving system to the mixer 409 A transmission distance of about 1.35 m can be secured. Since the transmission system is the same, the transmission distance from the mixer 403 to the antenna element 2 can be extended. Further, as shown in FIG. 13, the communicable distance can be extended by providing a plurality of low noise amplifiers. The signal processing circuit 4 may include only the low noise amplifier 407, or may include only the low noise amplifier 407 and the power amplifier 404. The communication circuit 30 may be configured to further secure the transmission distance by using a low loss such as an optical fiber via a waveguide or an optical electric converter. When only the low noise amplifier 407 and the power amplifier 404 are provided, it is preferable to use a low-loss communication circuit because the communicable distance can be further extended.

Next, with reference to FIGS. 14 to 18, an example of arranging the antenna elements of the branch connection type and the cascade connection type will be described.

FIG. 14 is a diagram schematically showing a branch connection type distributed antenna. The branch-connected distributed antenna 20 has an advantage of high communication efficiency because it can select the optimum antenna element 2 and communicate with a nearby mobile terminal by using the switch function of the signal processing circuit 4. There is. When a synthesizer / distributor such as a Wilkinson coupler is used, the optimum antenna element 2 cannot be selected, but the configuration can be simplified.

FIG. 15 is a diagram schematically showing a cascade connection type distributed antenna. Since the cascade-connected distributed antenna 20 can communicate with a nearby mobile terminal without using the function of the switch of the signal processing circuit 4, it has an advantage that the configuration is simplified and the reliability is high.

FIG. 16 is an enlarged view of a branch-connected distributed antenna. FIG. 17 is a diagram for explaining an image when a branch connection type distributed antenna is installed on the ceiling surface in the station yard. As shown in FIG. 17, for example, by arranging the branch connection type distributed antenna 20 on the wall surface forming the depression of the ceiling of the station platform, for example, at the tip of the transmission line 3 branched downward from the strip-shaped member 1. The antenna element 2 can be provided. As a result, the distance from the mobile terminal owned by the passenger waiting for the train at the platform of the station to the antenna element 2 can be made as close as possible, and the electric field strength is increased, so that the communication quality is improved.

FIG. 18 is a diagram for explaining an image when a cascade connection type distributed antenna is installed on the ceiling surface in the station yard. As shown in FIG. 18, for example, by arranging the cascade connection type distributed antenna 20 on the wall surface forming the depression of the ceiling of the station platform, the width of the strip-shaped member 1 in the direction orthogonal to the extending direction of the transmission line 3 is narrowed. Therefore, the coverage area can be expanded without impairing the design of the station.

Next, a modified example of the signal processing circuit will be described with reference to FIG. FIG. 19 is a diagram for explaining a modification of the signal processing circuit. FIG. 19 shows an example in which the signal processing circuit 4 is composed of a plurality of circuit boards, and each circuit board is installed on the wall 100 of the building on the transmission line 3 or in the vicinity of the transmission line 3. The number of the plurality of circuit boards is not limited to the illustrated example (3), and may be 2 or more. By configuring the signal processing circuit 4 with a plurality of circuit boards in this way, the signal processing circuit 4 can be installed according to the shape of the place where the distributed antenna 20 is installed, which impairs the design of a building or the like. It is possible to increase the available locations of the distributed antenna 20.

Next, a shield member that covers the surfaces of the signal processing circuit 4 and the strip-shaped member 1 of the distributed antenna 20 will be described with reference to FIGS. 20 and 21. FIG. 20 is a diagram showing a first modification of the strip-shaped member. FIG. 20 shows, for example, a shield member 40 that covers the entire surface of the strip-shaped member 1 formed of a flexible substrate. FIG. 21 is a diagram showing a second modification of the strip-shaped member. FIG. 21 shows a shield member 40 that covers the entire surface of the strip-shaped member 1 that is a combination of a flexible core member and a rigid core member. The shield member 40 is made of a metal or non-metal material having excellent thermal conductivity, which covers the entire surface of the band-shaped member 1 including the signal processing circuit 4. The material of the shield member 40 is, for example, the high thermosetting resin compound shown in (1) to (4) below, a carbon sheet, solder, an Ag—Cu sintered body, or the like. The material of the shield member 40 is not limited to these.

(1) A highly thermally conductive resin compound in which a thermally conductive filler is added to the polymer component. The polymer component is polysiloxane (silicone polymer), polyacrylic, polyolefin or the like. The method for producing the high thermal conductive resin compound is known as published in, for example, Japanese Patent No. 5089908 and Japanese Patent No. 5085050, and thus description thereof will be omitted.

(2) A sheet-shaped carbon sheet formed of carbon fiber or a composite material of carbon fiber and carbon. In recent years, carbon sheets have tended to be produced in large numbers using carbon fibers. Since the technology for mass production in a short time is being established, it can be classified as one of the materials having a relatively low thermal conductivity and being inexpensive. Further, the carbon sheet has a distributed antenna 20 that does not require a dedicated reflow furnace and does not require a process from heating to cooling even when the material unit price is higher than that of solder, Ag-Cu sintering, or the like. It has the effect of significantly reducing the time required to manufacture the solder.

(3) Solder (lead-free solder, etc.). Although it is necessary to use a reflow furnace or the like for solder, the material cost is low, so when mass-producing the distributed antenna 20, the heat is higher than that of the carbon sheet while suppressing the increase in the manufacturing cost of the distributed antenna 20 alone. The conductivity can be increased.

(4) Ag-Cu sintered body (Ag-Cu alloy containing Cu). The Ag—Cu sintered body is an expensive material because it contains Ag, but has high thermal conductivity and is suitable for heat dissipation of the signal processing circuit 4.

The shield member 40 is fixed to the band-shaped member 1 so as to be in close contact with the surfaces of the signal processing circuit 4 and the band-shaped member 1. The shield member 40 is preferably made of, for example, a material having a thermal conductivity higher than that of the signal processing circuit 4.

By providing the shield member 40, the heat generated in the signal processing circuit 4 is transmitted to the shield member 40 and radiated into the air from the surface of the shield member 40 (the surface opposite to the signal processing circuit 4 side). By providing the shield member 40 in this way, the heat conduction path generated in the signal processing circuit 4 increases, so that the possibility that the temperature of the signal processing circuit 4 exceeds the permissible temperature can be reduced. Further, since the shield structure covering the signal processing circuit 4 is formed, unnecessary radiation is reduced, the influence of noise on the equipment provided around the distributed antenna 20 can be reduced, and EMC (ElectroMagnetic Compatibility) performance is improved. Even when an electronic device is present near the distributed antenna 20, the shield member 40 covers the conductive portion 1a and the signal processing circuit 4 with the shield member 40, so that it becomes difficult for the conductive portion 1a and the electronic device to be capacitively coupled. , The influence on the antenna characteristics can be reduced.

Next, a configuration example of the flexible module will be described with reference to FIG. FIG. 22 is a diagram showing a configuration example of the flexible module. FIG. 22 shows that the flexible module is a module in which the shield member 40 is combined with the rigid flexible substrate described above. As shown in FIG. 22, the rigid flexible substrate includes, for example, a rigid core member 1B which is a rigid core member for mounting parts and the like, and a flexible portion 1A which is a bendable flexible core member, and is flexible with the rigid portion 1B. The shield member 40 is provided so as to cover the entire portion 1A. The rigid flexible board may be provided with a power amplifier 404, a switch 405, and the like that form the signal processing circuit 4. By providing such a flexible module on the wall 100 of a building or the like, the signal processing circuit 4 covers the shield member 40 to improve the EMC performance, and the distributed antenna 20 does not impair the design of the building or the like. You can increase the available locations of. When fixing the flexible module to the wall 100 of the building, the adhesive portion 60 may be used when the flexible module is permanently installed, or when the flexible module is temporarily installed, a binding band or the like is used. You may use it.

Next, with reference to FIG. 23, a configuration example in which the distributed antenna 20 is used as a repeater antenna will be described. FIG. 23 is a diagram showing a configuration example of a distributed antenna for a repeater. The distributed antenna 20 shown in FIG. 23 includes a receiving antenna 51 that receives radio waves transmitted from the transmitting antenna 50 connected to the base station 10. The antenna element 2 installed in a place different from the place where the receiving antenna 51 is arranged on the surface of the wall 100 causes the radio wave received by the receiving antenna 51 to be, for example, the direction of arrival of the radio wave to the receiving antenna 51. It relays (re-radiates) in a different direction from. With this configuration, even when the distance from the base station 10 to the distributed antenna 20 is long, the cost required for constructing the entrance line from the base station 10 to the distributed antenna 20 can be significantly reduced. As a matter of course, the same thing is established after exchanging transmission and reception. The method of using 5G radio waves as the entrance line is standardized as IAB (Integrated Access and Backhaul).

As described above, the distributed antenna according to the present embodiment is connected to the band-shaped member which is a band-shaped dielectric, the transmission line provided in the band-shaped member, and distributed in the band-shaped member. It is provided with a plurality of antenna elements. For example, in order to perform good wireless communication with a plurality of mobile terminals existing in spectator seats such as a stadium, it is desirable to shorten the distance from the plurality of antennas connected to the wireless base station to the mobile terminals. However, in the past, a plurality of antennas had to be installed on a specific structure in the stadium, for example, a roof existing above the spectators' seats or a pillar supporting the roof, and a plurality of mobile terminals and a plurality of antennas had to be installed. It is difficult to equalize the distance between each with the antenna. Therefore, there is a problem that the wireless communication quality is not stable. Further, there is a problem that the certainty of joining the transmission line to the antenna may be lowered. According to the distributed antenna according to the present embodiment, for example, a strip-shaped member can be arranged so as to bridge the upper space of the spectator seats of the stadium, or can be laid on the slope of the spectator seats. The coverage area can be expanded without affecting the. Further, the distributed antenna according to the present embodiment is provided with a signal processing circuit including a power amplifier 404, a low noise amplifier 407, and the like, so that the wireless communication level can be compensated even if the distance from the base station 10 becomes long.

(Effect of obstacles on radio wave propagation characteristics)
Next, the influence of obstacles on the propagation characteristics of radio waves will be described with reference to FIGS. 24 to 28. As described below, the inventors of the present invention conducted a test for investigating the influence of obstacles on the propagation characteristics of radio waves using the

conventional antennas

80A and 80B.

FIG. 24 is a diagram showing the arrangement of the

antennas

80A and 80B and the pillar 70 in this test. As shown in FIG. 24, the inventors of the present invention arranged the conventional antenna 80A and the conventional antenna 80B so as to face each other. Here, the inventors of the present invention set the separation distance between the antenna 80A and the antenna 80B to 500 mm. Further, the inventors of the present invention installed a columnar pillar 70 as an example of an obstacle at an intermediate position between the antenna 80A and the antenna 80B. Then, the inventors of the present invention tested the influence of the presence or absence of the pillar 70 and the diameter of the pillar 70 on the propagation characteristics of the radio wave transmitted from the antenna 80A to the antenna 80B.

FIG. 25 is a diagram showing the configurations of the

antennas

80A and 80B used in this test. In this test, 28 GHz band patch antennas were used as the

antennas

80A and 80B. As shown in FIG. 25, the

antennas

80A and 80B have a substrate 82 and an antenna element 84. As shown in FIG. 25, in this test, the shape of the substrate 82 was square, and the length of one side of the substrate 82 was 10.0 mm. Further, as shown in FIG. 25, in this test, the shape of the antenna element 84 was square, and the length of one side of the antenna element 84 was 2.6 mm.

FIG. 26 is a diagram showing the antenna characteristics (XY surface directivity) of the

antennas

80A and 80B used in this test. As shown in FIG. 26, the

antennas

80A and 80B have strong directivity in the X-axis direction (perpendicular direction of the surface of the antenna element 84). Further, the

antennas

80A and 80B can obtain 5.5 dBi in the X-axis direction as the maximum gain in the 28 GHz band.

FIG. 27 is a table showing the measurement results (S21) by this test for each installation condition of the pillar 70. FIG. 28 is a graph showing the measurement results (S21) in this test for each installation condition of the pillar 70. As shown in FIGS. 27 and 28, in this test, the propagation is propagated from the antenna 80A to the antenna 80B in the case where the pillar 70 is not installed and the case where the diameter of the pillar 70 is 50 mm, 100 mm, and 200 mm, respectively. The transmission coefficient (S21) of the radio wave was measured.

As shown in FIGS. 27 and 28, in the presence of the pillar 70, "-39.6 dB" was obtained as the transmission coefficient (S21) of the radio wave in the 28 GHz band by this test. On the other hand, when the pillar 70 having a diameter of 50 mm was present, "-44.4 dB" was obtained as the transmission coefficient (S21) of the radio wave in the 28 GHz band. Further, when the pillar 70 having a diameter of 100 mm was present, "-52.8 dB" was obtained as the transmission coefficient (S21) of the radio wave in the 28 GHz band. Further, in the presence of the pillar 70 having a diameter of 200 mm, "-73.7 dB" was obtained as the transmission coefficient (S21) of the radio wave in the 28 GHz band. From these measurement results, it was found from this test that the presence of the pillar 70 reduces the value of S21 (that is, it becomes difficult for radio waves to reach). Further, in this test, it was found that the value of S21 decreases (that is, it becomes difficult for radio waves to reach) as the diameter of the pillar 70 increases.

That is, from this test, it was found that when an obstacle such as a pillar exists on the propagation path of the radio wave radiated from the antenna, it becomes difficult for the radio wave to reach the area behind the obstacle (blind spot). In particular, the millimeter-wave band radio waves used in 5G and the like have low wraparound to obstacles, so that they are difficult to reach the area that becomes the blind spot of obstacles. Therefore, the inventors of the present invention have invented the flexible antenna 20A described below for the purpose of allowing radio waves to reach each of a plurality of directions around an obstacle such as a pillar more reliably.

(Flexible antenna 20A)
Next, the flexible antenna 20A will be described as another example of the distributed antenna 20 with reference to FIGS. 29 to 44. The flexible antenna 20A can be installed on a pillar 70 (an example of a "columnar installation object") such as a traffic light, a street light, or a utility pole. The flexible antenna 20A can be used as, for example, a 5G antenna for a base station.

FIG. 29 is a plan view of the flexible antenna 20A according to the embodiment. As shown in FIG. 29, the flexible antenna 20A includes a flexible substrate 26 and a plurality of antennas ANT1 to ANT8.

The flexible substrate 26 is a flexible sheet-like member. The flexible substrate 26 has a horizontally long rectangular shape in a plan view. The plurality of antennas ANT1 to ANT8 are arranged side by side at equal intervals in the horizontal direction HD on the surface of the flexible substrate 26. Each of the plurality of antennas ANT1 to ANT8 has a vertically polarized wave antenna 22A and a horizontally polarized wave antenna 22B.

The vertically polarized antenna 22A has a plurality of (8 in the example shown in FIG. 29) antenna elements 2 arranged side by side in the vertical VD, and a transmission line 3 extending linearly in the vertical VD. .. Each of the plurality of antenna elements 2 included in the vertically polarized wave antenna 22A has a branch path of the transmission line 3 connected at a right angle to the lower side thereof.

The horizontally polarized antenna 22B has a plurality of (8 in the example shown in FIG. 29) antenna elements 2 arranged side by side in the vertical VD. It has a transmission line 3 extending linearly in the vertical direction VD. Each of the plurality of antenna elements 2 included in the horizontally polarized wave antenna 22B has a branch path of the transmission line 3 connected at a right angle to the left side thereof.

Each of the plurality of vertically polarized wave antennas 22A and the plurality of horizontally polarized wave antennas 22B has independent connection ports at the lower end of the transmission line 3. As a result, the signal processing circuit 4 connected to the flexible antenna 20A independently transmits radio waves to each of the plurality of vertically polarized antennas 22A and the plurality of horizontally polarized antennas 22B via the plurality of connection ports. Can be used for radiation.

Further, in the vertically polarized antenna 22A and the horizontally polarized antenna 22B, the straight portion extending in the vertical direction VD of the transmission line 3 has a shape in which the band width gradually narrows toward the tip. As a result, the vertically polarized wave antenna 22A and the horizontally polarized wave antenna 22B equalize the energy supplied from the connection port of the transmission line 3 to each of the plurality of antenna elements 2 connected to the transmission line 3. Can be distributed to.

FIG. 30 is a diagram showing an example of a cross-sectional configuration of the flexible antenna 20A according to the embodiment. In the example shown in FIG. 30, the flexible antenna 20A has a flexible substrate 26, an antenna element 24, a transmission line 25, and a ground layer 27.

The flexible substrate 26 is a flexible, resin-made, thin film-like member. For example, the thickness of the flexible substrate 26 is 1 μm to 300 μm. Further, for example, the flexible substrate 26 includes fluorine, COP (CycloOlefin Polymer), PET (Polyethylene terephthalate), PEN (polyethylene naphthalate), polyimide, Peak (polyetheretherketone), LCP (Liquid Crystal Polymer), and other composite materials. And other resin materials are used.

The antenna element 24 and the transmission line 25 are formed in a thin film on the upper surface of the flexible substrate 26. For example, the thickness of the antenna element 24 and the transmission line 25 is 1 nm to 32 μm. Further, for example, the antenna element 24 and the transmission line 25 are formed by using a conductive material such as copper.

The ground layer 27 is formed in a thin film on the lower surface of the flexible substrate 26. For example, the thickness of the ground layer 27 is 1 nm to 32 μm. Further, for example, the ground layer 27 is formed by using a conductive material such as copper.

FIG. 31 is a diagram showing another example of the cross-sectional configuration of the flexible antenna 20A according to the embodiment. In the example shown in FIG. 31, the flexible antenna 20A has a first flexible substrate 26A and a second flexible substrate 26B which are overlapped with each other instead of the flexible substrate 26 shown in FIG.

In the example shown in FIG. 31, the antenna element 24 is formed on the upper surface of the first flexible substrate 26A. Further, in the example shown in FIG. 31, the transmission line 25 is formed between the first flexible substrate 26A and the second flexible substrate 26B. Further, in the example shown in FIG. 31, the ground layer 27 is formed on the lower surface of the second flexible substrate 26B.

FIG. 32 is a diagram showing an example of installation of the flexible antenna 20A according to the embodiment on the pillar 70. FIG. 33 is a cross-sectional view taken along the line XY of the flexible antenna 20A and the pillar 70 shown in FIG.

As shown in FIGS. 32 and 33, since the flexible antenna 20A has flexibility, it can be installed by being wound around the outer peripheral surface 70A of the pillar 70. As a result, the flexible antenna 20A is vertically polarized and horizontally polarized in each of the plurality of directions (8 directions in the case of the configuration shown in FIG. 29) centered on the pillar 70 by each of the plurality of antennas ANT1 to ANT8. Can radiate each of them.

In particular, in the examples shown in FIGS. 32 and 33, the plurality of antennas ANT1 to ANT8 are arranged on the outer peripheral surface 70A of the pillar 70 at intervals of 45 °. Therefore, the flexible antenna 20A can radiate vertically polarized waves and horizontally polarized waves in each of the eight directions at 45 ° intervals centered on the pillar 70 by each of the plurality of antennas ANT1 to ANT8. it can.

Thereby, according to the flexible antenna 20A according to the embodiment, the radio waves can be more reliably reached in each of the plurality of directions around the pillar 70.

Further, in the flexible antenna 20A according to the embodiment, each of the plurality of antennas ANT1 to ANT8 has an independent connection port. Therefore, the flexible antenna 20A according to the embodiment radiates radio waves only in a necessary direction by driving (powering) a part of a plurality of antennas ANT1 to ANT8 according to the purpose of use, installation location, and the like. Can be done.

Further, the flexible antenna 20A according to the embodiment is in the form of a thin sheet having flexibility, and can be flexibly deformed along the installation surface. Therefore, the flexible antenna 20A according to the embodiment is not limited to columnar columns, but is applied to various other columnar installation objects (for example, prisms, wall surfaces bent at right angles, wall surfaces having an uneven shape, etc.). , It is possible to install the structure so that it does not protrude from the installation surface of the structure.

The flexible antenna 20A is fixed to the outer peripheral surface 70A of the pillar 70 by an arbitrary fixing method (for example, adhesive, double-sided tape, etc.). Further, the flexible antenna 20A may be fixed to the outer peripheral surface 70A of the pillar 70 by closing one end and the other end to form an annular shape.

Further, the surface of the flexible antenna 20A is protected from rainwater, ultraviolet rays, etc. by a protective film, a protective cover, etc. before it is installed on the outer peripheral surface 70A of the pillar 70 or after it is installed on the outer peripheral surface 70A of the pillar 70. May be done.

Further, when the diameter of the pillar 70 to which the flexible antenna 20A is to be installed is determined, it is preferable that the width of the flexible antenna 20A has a length corresponding to the circumferential length of the outer peripheral surface of the pillar 70. In this case, when the flexible antenna 20A is installed on the pillar 70, one end and the other end of the flexible antenna 20A in the horizontal direction may overlap each other or may be slightly separated from each other. Further, when the flexible antenna 20A is installed on a pillar 70 having a predetermined diameter, it is preferable that a plurality of antennas are arranged at a predetermined angle (360 ° ÷ number of antennas) intervals about the pillar 70.

FIG. 34 is a diagram showing a first modification of the antenna pattern in the flexible antenna 20A according to the embodiment. FIG. 35 is a diagram showing a second modification of the antenna pattern in the flexible antenna 20A according to the embodiment.

In the example shown in FIGS. 34 and 35, the flexible antenna 20A has four antennas arranged side by side at equal intervals in the horizontal direction HD on the surface of the flexible substrate 26. Each of the four antennas has three antenna elements 2 arranged side by side in the vertical VD. In each of the four antennas, the three antenna elements 2 are connected in series by a transmission line 3 extending linearly in the vertical VD.

As a result, when the flexible antenna 20A shown in FIGS. 34 and 35 is installed on the outer peripheral surface 70A of the pillar 70, each of the four antennas makes one direction with respect to each of the four directions centered on the pillar 70. Vertically polarized light can be radiated by three antenna elements 2 per unit. In particular, when the flexible antenna 20A shown in FIGS. 34 and 35 is installed on the outer peripheral surface 70A of a pillar 70 having a predetermined diameter, four antennas may be arranged at 90 ° intervals with respect to the outer peripheral surface 70A. it can. In this case, the flexible antenna 20A shown in FIGS. 34 and 35 can radiate vertically polarized light in each of the four directions at 90 ° intervals centered on the pillar 70 by each of the four antennas.

In the flexible antenna 20A shown in FIG. 35, each of the four antennas has an independent connection port. Therefore, the flexible antenna 20A shown in FIG. 35 can drive each of the four antennas individually, that is, can radiate radio waves only in a specific direction, if necessary. Further, the flexible antenna 20A shown in FIG. 35 can transmit a plurality of different types of signals simultaneously or with a time lag by the four antennas. For example, the flexible antenna 20A shown in FIG. 35 can also be used for MIMO (multiple-input and multiple-output), beamforming, and the like.

Further, the flexible antenna 20A shown in FIGS. 34 and 35 is vertical by adjusting the interval between the vertical VDs of the antenna elements 2 arranged side by side in the vertical direction VD and adjusting the phase in which the antenna element 2 is fed. The direction of the beam in the direction VD (elevation / depression angle direction) can be controlled.

For example, by arranging the antenna elements 2 so that the vertical VD intervals of the antenna elements 2 are approximately one wavelength in the electrical length of the transmission line 3, that is, they are in phase with each other, the antenna elements 2 are arranged at 0 ° in the elevation / depression angle direction. The direction of the beam can be controlled.

Further, for example, by arranging the antenna element 2 so that the interval between the vertical VDs of the antenna element 2 is longer than one wavelength by the electric length in the transmission line 3, that is, the phase is delayed, the beam direction is elevated. It can be controlled (up-tilted) in the direction.

Further, for example, by arranging the antenna element 2 so that the interval between the vertical VDs of the antenna element 2 is shorter than one wavelength in the electrical length of the transmission line 3, that is, the phase advances, the beam direction is depressed. It can be controlled in the direction (down tilt).

This also applies to the

flexible antennas

22A and 22B shown in FIGS. 29 and 32, and the beam direction of the vertical VD can be controlled by adjusting the phase fed to each of the antenna elements 2.

When controlling the beam direction to 0 ° in the elevation / depression angle direction, it is preferable that the vertical VD interval is 0.96 wavelength or more and 1.04 wavelength or less in terms of the electrical length of the transmission line 3.

When controlling (up-tilting) the beam direction in the elevation direction, it is preferable that the vertical VD interval is 1.05 wavelength or more and 1.50 wavelength or less in terms of the electrical length of the transmission line 3.

When controlling the beam direction in the depression angle direction (downtilt), it is preferable that the vertical VD interval is 0.50 wavelength or more and 0.95 wavelength or less in terms of the electrical length of the transmission line 3.

On the other hand, the flexible antenna 20A shown in FIG. 34 has one connection port connected to each of the four antennas. Therefore, the flexible antenna 20A shown in FIG. 34 can drive each of the four antennas at the same time by supplying a drive signal from the signal processing circuit 4 to one connection port, that is, in four directions. Radio waves can be emitted to each at the same time.

FIG. 36 is a diagram showing a third modification of the antenna pattern in the flexible antenna 20A according to the embodiment.

In the example shown in FIG. 36, the flexible antenna 20A has four antenna elements 2 arranged side by side in the vertical direction VD at each of the four positions in the horizontal direction HD on the surface of the flexible substrate 26. That is, the flexible antenna 20A shown in FIG. 36 has 16 antenna elements 2 arranged in a 4 × 4 matrix on the surface of the flexible substrate 26. Further, in the flexible antenna 20A shown in FIG. 36, an independent transmission line 3 is provided for each of the 16 antenna elements 2. Each of the 16 antenna elements 2 is connected to the left side or the right side at a right angle to the end of the transmission line 3 bent at a right angle to the horizontal HD.

As a result, when the flexible antenna 20A shown in FIG. 36 is installed on the outer peripheral surface 70A of the pillar 70, a part of the four antenna elements 2 or a part of the four antenna elements 2 in each direction with respect to each of the four directions centered on the pillar 70. All can radiate horizontally polarized waves.

In particular, when the flexible antenna 20A shown in FIG. 36 is installed on the outer peripheral surface 70A of a pillar 70 having a predetermined diameter, four antenna elements 2 are arranged at 90 ° intervals with respect to the outer peripheral surface 70A. Can be done. In this case, the flexible antenna 20A shown in FIG. 36 is horizontally polarized using a part or all of the four antenna elements 2 in each direction with respect to each of the four directions at 90 ° intervals centered on the pillar 70. Can be radiated.

In the flexible antenna 20A shown in FIG. 36, each of the 16 antenna elements 2 has an independent connection port. Therefore, the flexible antenna 20A shown in FIG. 36 can individually drive each of the 16 antenna elements 2 as needed. Thereby, for example, in the flexible antenna 20A shown in FIG. 36, the beamforming direction can be freely controlled in each of the vertical direction and the horizontal direction by an arbitrary plurality of antenna elements 2. Further, for example, the flexible antenna 20A shown in FIG. 36 can transmit a plurality of different types of signals simultaneously or with a time lag by an arbitrary plurality of antenna elements 2.

FIG. 37 is a diagram showing a first example of antenna characteristics of the flexible antenna 20A according to the embodiment. In FIG. 37, the flexible antenna 20A (length 100 mm, width 430 mm) according to the embodiment is installed on the outer peripheral surface 70A of the pillar 70 (diameter 140 mm), and the flexible antenna 20A is provided with eight antennas at intervals of 45 °. It represents the antenna characteristics of each of the eight antennas on the XY plane in the 28 GHz band. Note that FIG. 37A shows the antenna characteristics of the vertically polarized wave antenna 22A. Further, FIG. 37B shows the antenna characteristics of the horizontally polarized wave antenna 22B.

As shown in FIG. 37A, according to the flexible antenna 20A according to the embodiment, the eight antennas provide a sufficient gain (maximum gain of 12.5 dBi) in each of the eight directions having a 45 ° interval around the pillar 70. Can radiate vertically polarized light with.

Further, as shown in FIG. 37B, according to the flexible antenna 20A according to the embodiment, the eight antennas provide a sufficient gain (maximum gain 10.) In each of the eight directions having a 45 ° interval around the pillar 70. It can emit horizontally polarized waves with 4 dBi).

FIG. 38 is a diagram showing a second example of the antenna characteristics of the flexible antenna 20A according to the embodiment. In FIG. 38, the flexible antenna 20A (length 100 mm, width 430 mm) according to the embodiment is installed on the outer peripheral surface 70A of the pillar 70 (diameter 140 mm), and the flexible antenna 20A is provided with six antennas at intervals of 60 °. It represents the antenna characteristics of each of the six antennas on the XY plane in the 28 GHz band. Note that FIG. 38A shows the antenna characteristics of the vertically polarized wave antenna 22A. Further, FIG. 38B shows the antenna characteristics of the horizontally polarized wave antenna 22B.

As shown in FIG. 38A, according to the flexible antenna 20A according to the embodiment, the six antennas provide a sufficient gain (maximum gain of 12.5 dBi) in each of the six directions having a 60 ° interval around the pillar 70. Can radiate vertically polarized light with.

Further, as shown in FIG. 38B, according to the flexible antenna 20A according to the embodiment, the six antennas provide a sufficient gain (maximum gain 10.) In each of the six directions having a 60 ° interval around the pillar 70. It can emit horizontally polarized waves with 4 dBi).

FIG. 39 is a diagram showing a third example of the antenna characteristics of the flexible antenna 20A according to the embodiment. In FIG. 39, the flexible antenna 20A (length 100 mm, width 430 mm) according to the embodiment is installed on the outer peripheral surface 70A of the pillar 70 (diameter 140 mm), and the flexible antenna 20A is provided with four antennas at 90 ° intervals. In this case, the antenna characteristics in the 28 GHz band of each of the four antennas on the XY plane are represented. Note that FIG. 39A shows the antenna characteristics of the vertically polarized wave antenna 22A. Further, FIG. 39B shows the antenna characteristics of the horizontally polarized wave antenna 22B.

As shown in FIG. 39A, according to the flexible antenna 20A according to the embodiment, the four antennas provide a sufficient gain (maximum gain of 12.5 dBi) in each of the four directions having a 90 ° interval around the pillar 70. Can radiate vertically polarized light with.

Further, as shown in FIG. 39B, according to the flexible antenna 20A according to the embodiment, the four antennas provide a sufficient gain (maximum gain 10.) In each of the four directions having a 90 ° interval around the pillar 70. It can emit horizontally polarized waves with 4 dBi).

FIG. 40 is a diagram showing a fourth example of antenna characteristics of the flexible antenna 20A according to the embodiment. In FIG. 40, the flexible antenna 20A (length 100 mm, width 430 mm) according to the embodiment is installed on the outer peripheral surface 70A of the pillar 70 (diameter 140 mm), and the flexible antenna 20A is provided with three antennas at 120 ° intervals. In this case, it represents the antenna characteristics in the 28 GHz band of each of the three antennas on the XY plane. Note that FIG. 40A shows the antenna characteristics of the vertically polarized wave antenna 22A. Further, FIG. 40B shows the antenna characteristics of the horizontally polarized wave antenna 22B.

As shown in FIG. 40A, according to the flexible antenna 20A according to the embodiment, the three antennas provide a sufficient gain (maximum gain of 12.5 dBi) in each of the three directions having a 120 ° interval around the pillar 70. Can radiate vertically polarized light with.

Further, as shown in FIG. 40B, according to the flexible antenna 20A according to the embodiment, the three antennas provide a sufficient gain (maximum gain 10.) In each of the three directions having a 120 ° interval around the pillar 70. It can emit horizontally polarized waves with 4 dBi).

FIG. 41 is a diagram showing a fifth example of antenna characteristics of the flexible antenna 20A according to the embodiment. In FIG. 41, the flexible antenna 20A (length 100 mm, width 430 mm) according to the embodiment is installed on the outer peripheral surface 70A of the pillar 70 (diameter 140 mm), and the flexible antenna 20A is provided with two antennas at 180 ° intervals. In this case, it represents the antenna characteristics of each of the two antennas on the XY plane in the 28 GHz band. Note that FIG. 41A shows the antenna characteristics of the vertically polarized wave antenna 22A. Further, FIG. 41B shows the antenna characteristics of the horizontally polarized wave antenna 22B.

As shown in FIG. 41A, according to the flexible antenna 20A according to the embodiment, the two antennas provide a sufficient gain (maximum gain of 12.5 dBi) in each of the two directions having a 180 ° interval around the pillar 70. Can radiate vertically polarized light with.

Further, as shown in FIG. 41B, according to the flexible antenna 20A according to the embodiment, the two antennas provide a sufficient gain (maximum gain 10. It can emit horizontally polarized waves with 4 dBi).

Due to the antenna characteristics shown in FIGS. 37 to 41, the flexible antenna 20A according to the embodiment preferably has at least two antennas and has three or more antennas in order to cover all directions around the pillar 70. Is more preferable.

FIG. 42 is a diagram showing a fourth modification of the antenna pattern in the flexible antenna 20A according to the embodiment. FIG. 43 is a diagram showing an example of installation of the flexible antenna 20A shown in FIG. 42 on the pillar 70.

In the example shown in FIGS. 42 and 43, the flexible antenna 20A has one antenna ANT1 extending in the horizontal direction HD on the surface of the flexible substrate 26. The antenna ANT1 has eight antenna elements 2 arranged side by side in the horizontal direction HD. In the antenna ANT1, the eight antenna elements 2 are connected in series by a transmission line 3 extending linearly in the horizontal direction HD.

As a result, when the flexible antenna 20A shown in FIGS. 42 and 43 is installed on the outer peripheral surface 70A of the pillar 70 as shown in FIG. 43, each of the eight antenna elements 2 causes the pillar 70 to be the center 8 Horizontally polarized waves can be emitted in each of the two directions.

In particular, the flexible antenna 20A shown in FIGS. 42 and 43 has one connection port connected to each of the eight antenna elements 2. Therefore, the flexible antenna 20A shown in FIGS. 42 and 43 can drive each of the eight antenna elements 2 at the same time by supplying a drive signal from the signal processing circuit 4 to one connection port, that is, , Can emit horizontally polarized light in each of the eight directions at the same time.

FIG. 44 is a diagram showing an example of antenna characteristics of the flexible antenna 20A shown in FIG. 42. FIG. 44A shows the antenna characteristics of the flexible antenna 20A (length 15 mm, width 60 mm) shown in FIG. 42 in the 28 GHz band of the antenna ANT1 on the YX plane. FIG. 44B shows the antenna characteristics of the antenna ANT1 on the YX surface in the 28 GHz band when the flexible antenna 20A (length 15 mm, width 60 mm) shown in FIG. 42 is installed on the outer peripheral surface 70A of the pillar 70 (diameter 25 mm). There is.

As shown in FIG. 44B, according to the flexible antenna 20A shown in FIG. 42, the antenna ANT1 having the eight antenna elements 2 has a sufficient gain (maximum gain 1 dBi) in each of the eight directions centered on the pillar 70. Can radiate horizontally polarized waves with.

The configuration shown in the above-described embodiment shows an example of the contents of the present disclosure, can be combined with another known technique, and is one of the configurations as long as it does not deviate from the gist of the present disclosure. It is also possible to omit or change the part.

This international application is filed on November 6, 2019, Japanese Patent Application No. 2019-201844, Japanese Patent Application No. 2019-225319 filed on December 13, 2019, and January 22, 2020. It claims priority based on Japanese Patent Application No. 2020-007983 filed in Japan, and the entire contents of the application are incorporated into this international application.

1: Band-shaped member 1b1: First surface 1b2: Second surface 1A: Flexible part 1B: Rigid part 1a: Conductive part 1b: Core part 2:

Antenna element

3,3a: Transmission line 4: Signal processing circuit 10: Base station 11 : Fin base 20: Distributed antenna 30: Communication line 40: Shield member 50: Transmitting antenna 51: Receiving antenna 60: Adhesive part 100: Wall 201: Convex part 202: Flat surface 300: Distributed antenna system 400: Amplifier module 402: Local transmitter 403: Mixer 404: Power amplifier 405: Switch 406: Directional coupler 407: Low noise amplifier 408: Switch 409: Mixer 20A: Flexible antenna ANT1 to ANT8: Antenna 22A: Vertical polarization antenna 22B: Horizontal polarization Antenna 24: Antenna element 25: Transmission line 26: Flexible substrate 26A: First flexible substrate 26B: Second flexible substrate 27: Ground layer 70: Pillar 70A: Outer

peripheral surface

80A, 80B: Antenna 82: Substrate 84: Antenna element

Claims

A strip-shaped member having a plate-shaped dielectric, a first surface which is one surface of the dielectric, and a second surface opposite to the first surface, and a strip-shaped member extending in a strip shape.
A transmission line provided on any of the first surface and the second surface, or between the first surface and the second surface.
It is electrically connected to the transmission line and dispersedly arranged on any of the first surface and the second surface, or is electrically connected to the transmission line and is electrically connected to the first surface and the first surface. Multiple antenna elements distributed between the two surfaces and
Distributed antenna with.
The transmission line is
A first transmission line and a second transmission line branching from the first transmission line are provided.
The distributed antenna according to claim 1, wherein the antenna element is connected to the second transmission line.
The distributed antenna according to claim 1, wherein the antenna element is provided on the transmission line.
The distributed antenna according to any one of claims 1 to 3, wherein the strip-shaped member is a flexible member having flexibility.
The distributed antenna according to any one of claims 1 to 3, wherein the strip-shaped member has a flexible member having flexibility and a rigid core member.
The distributed antenna according to claim 5, wherein the rigid core member and / or the flexible member is provided with a signal processing circuit for processing a signal transmitted to the transmission line.
The distributed antenna according to any one of claims 1 to 6, further comprising a signal processing circuit provided on the strip-shaped member and having an amplifier for amplifying a signal transmitted to the transmission line.
The distributed antenna according to any one of claims 1 to 7, further comprising a signal processing circuit provided on the strip-shaped member and having a mixer for up-converting or down-converting a signal transmitted to the transmission line.
The DAC, which is provided on the strip-shaped member and is a converter that converts a digital signal transmitted from a base station into an analog signal and transmits it to a mixer, and a DAC that converts an analog signal transmitted from the mixer into a digital signal to the base station. The distributed antenna according to any one of claims 1 to 8, further comprising a signal processing circuit having an ADC which is a converter for transmitting.
The distributed antenna according to any one of claims 1 to 9, further comprising a signal processing circuit provided on the strip-shaped member and having a local oscillator which is a local signal source for a mixer.
A signal processing circuit provided on the strip-shaped member and processing a signal transmitted to the transmission line, and a signal processing circuit.
A power wiring provided on the strip-shaped member to supply power for driving the signal processing circuit, and
The distributed antenna according to any one of claims 1 to 10.
A signal processing circuit provided on the strip-shaped member and processing a signal transmitted to the transmission line, and a signal processing circuit.
A member that covers at least the signal processing circuit and
The distributed antenna according to any one of claims 1 to 11.
A signal processing circuit provided on the strip-shaped member and having two or more functions for processing a signal transmitted to the transmission line is provided.
The distributed antenna according to any one of claims 1 to 12, wherein the signal processing circuit is composed of a plurality of circuit boards having two or more functions.
Equipped with a receiving antenna that receives radio waves transmitted from the base station
The distributed antenna according to any one of claims 1 to 13, wherein the antenna element relays a radio wave received by the receiving antenna to a place different from the place where the receiving antenna is arranged.
The distributed antenna according to any one of claims 1 to 14, further comprising a member covering the transmission line.
A plurality of antennas arranged horizontally side by side on the surface of the strip-shaped member are provided.
Each of the plurality of antennas has one or more of the antenna elements.
The distributed antenna according to claim 4.
A claim characterized in that radio waves can be radiated in each of a plurality of directions around the installation object by each of the plurality of antennas by wrapping the antenna around the outer peripheral surface of the columnar installation object. Item 16. The distributed antenna according to item 16.
At each of the plurality of horizontal positions on the surface of the strip-shaped member,
Antenna for vertical polarization and
The distributed antenna according to claim 16 or 17, further comprising a horizontally polarized antenna.
Each of the plurality of antennas
The distributed antenna according to any one of claims 16 to 18, wherein the antenna elements are arranged side by side in the vertical direction.
The distributed antenna according to any one of claims 16 to 19, wherein the transmission line is one transmission line connected to each of the plurality of antennas.
The distributed antenna according to any one of claims 16 to 19, wherein the transmission line is a plurality of transmission lines provided for each of the plurality of antennas.
The distributed antenna according to any one of claims 16 to 21, wherein the plurality of antennas are arranged side by side at equal intervals in the horizontal direction.
The plurality of antenna elements are provided side by side in the horizontal direction on the surface of the strip-shaped member.
The distributed antenna according to claim 4, wherein the transmission line includes one transmission line connected to each of the plurality of antenna elements.
The distributed antenna according to claim 23, wherein the plurality of antenna elements are arranged side by side at equal intervals in the horizontal direction.
The plurality of antenna elements are arranged in a matrix on the surface of the strip-shaped member so as to be arranged in each of the horizontal direction and the vertical direction.
The transmission line is a plurality of transmission lines provided for each antenna element for each of the plurality of antenna elements.
The distributed antenna according to claim 4, wherein the antenna is provided.